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In the present study, Dendrobium officinale polysaccharides (DOPs) are incorporated into sodium alginate (SA) for the development of SA‐DOPs films. The physical, mechanical, and functional properties of SA‐DOPs composite films and their ability to preserve fresh grapes are investigated. The results reveal that the addition of DOPs can significantly enhance the thickness, swelling ratio, tensile strength, elongation at break, and thermal stability of the films (p < 0.05) whereas the water solubility and water vapor permeability are decreased. Fourier transform‐infrared (FT‐IR) spectroscopy results reflect interaction of chemical groups and bonds between SA and DOPs. The result of scanning of electron microscopy (SEM) indicates smooth for SA‐DOPs films while control film exhibits rough. The SA‐DOPs films exhibit potential antioxidant effects on 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) and 2,2'‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid) (ABTS) free radicals. Furthermore, the composite films exhibit remarkable inhibition of the growth of Escherichia coli and Staphylococcus aureus (p < 0.05). In addition, the SA‐DOPs coatings can effectively reduce weight loss, inhibit polyphenol oxidase activity, extend the shelf life of the grapes at room temperature (25 ± 1 °C) for 14 days. These results indicate that the SA‐DOPs edible coatings might be a promising candidate in food preservation industries. [ABSTRACT FROM AUTHOR]

Corn stover is a valuable feedstock for non-grain sugar production. Each anatomical part has different composition and structural propertied. In this study, corn stover was divided into four parts (stem, leaf, husk, and ear). Their response to ball milling pretreatment and potential for sugar production by enzymatic hydrolysis were studied. Among four parts, the husk obtained the highest monosaccharide concentration due to its lower crystallinity and more suitable chemical composition. Ball milling pretreatment can enhance their structural properties significantly and increase sugar yield. At 20% solid loadings, the monosaccharides concentration in all parts exceeded 80 g·L−1. However, due to the larger particle size, the husk had a poor response to ball milling pretreatment. In contrast, the best response was observed in stem due to the least particle size and lots of cavity structure. Therefore, the enzymatic hydrolysis efficiency of ball milled stem was the highest. Furthermore, the lignin content among various parts before ball milling was the critical factor for the difference in enzymatic hydrolysis efficiency, so as the ash content of the leaves, the crystallinity and water retention value of the stem. After ball milling, higher crystallinity, xylan content, D(10) and water retention value were the key factors leading to low enzymatic hydrolysis conversion of husk. This study provided a guidance for the better corn stover sugar production. [Display omitted] • Husk has the best sugar production potential before ball milling. • Stem obtains the best ball milling effect. • The high solids effect of ball milled husk is more severe than that stem. • The properties of leaf and ear are similar. • The key factors affecting enzymatic hydrolysis vary with sample and pretreatment. [ABSTRACT FROM AUTHOR]

Acidic vinegar residue (VR) and toxic hexavalent chromium (Cr(VI)) are unfavorable substances due to their toxicity against the environment. In this study, modified biochar was prepared to investigate the removal mechanisms of Cr(VI). The results showed that ZnCl 2 could yield highly aromatic products with improved pore structures. The adsorption capacity of modified biochar reached the highest efficiency (236.81 mg g−1) when the mass ratio of ZnCl 2 /VR was 1, which is higher than the control (9.96 mg g−1). In addition, Cr(VI) adsorption coexisted with physical and chemical adsorption. The mechanisms of modified biochar to Cr(VI) removal included electrostatic attraction, pore filing, reduction and surface complexation. Notably, as a fermented product, VR biochar was a nitrogen-rich product; the formation of the amino group could provide a direct solid site for Cr(VI) adsorption. Subsequently, amorphous silica could be converted into silanol to provide additional adsorption sites. This work establishes the theoretical basis for efficient Cr(VI) removal and VR reuse. [Display omitted] • Vinegar residue biochar (VB) is nitrogen and silicon-rich product. • ZnCl 2 can inhibit the production of toxic nitriles in biochar. • Modified VB exhibits excellent ability to remove Cr (VI) (236.81 mg g−1). • Si-O of VB can be converted into Si-OH to provide indirect adsorption sites. • Mechanisms of Cr(VI) removal included physical and chemical adsorption. [ABSTRACT FROM AUTHOR]

The addition of soy sauce residue (SSR) during soybean paste fermentation usually reduces the flavor quality due to high content of fibers. Steam explosion (SE) pretreatment is an effective way to promote the fiber degradation. In this study, SE-pretreated SSR was investigated and exploited during soybean paste fermentation. SE pretreatment increased the numbers of holes and the surface irregularity, resulting in a more pronounced wrinkled surface and looser internal structure than other pretreatments. Over half of cellulose and 10 percentage of hemicellulose were released from the dense structure of SE-pretreated SSR. The addition of 3–10 percentage of the SE-pretreated SSR was more suitable for soybean paste fermentation. The flavor formation of SSR during soybean paste fermentation was enhanced by SE pretreatment. In brief, SE pretreatment of SSR improve the quality of soybean paste. • The dense structure of soy sauce residue was destroyed by steam explosion (SE). • A clearer wrinkled surface and looser inner structure can be formed by SE. • More cellulose and hemicellulose were exposed by SE pretreatment. • Soybean paste flavor was improved by adding 3–10% SE pretreated soy sauce residue. • SE pretreated soy sauce residue was more suitable for soybean paste fermentation. [ABSTRACT FROM AUTHOR]

A correction to this paper has been published: https://doi.org/10.1007/s00340-021-07611-y [ABSTRACT FROM AUTHOR]

A polarization-maintaining (PM) fiber-coupled acousto-optic modulator (AOM) was used, in the present work, to tailor the stable 3.523 picosecond (ps) mode-locked pulses generated by an all PM fiber oscillator. The pulse clusters with 7.315 MHz, 731.5 kHz, and 73.15 kHz of repetition rate were obtained. The number of pulses in each pulse cluster could be adjusted from 1 to 6. Through the harmonic mode-locked (HML) technology, the tunability of the fiber laser was remarkably improved. Ultimately, the tunable number of pulses were extended to 8, 10, and 12, and obtained 4, 6 and 8 pulses with equal amplitude respectively, providing a greater flexibility than previous methods. [ABSTRACT FROM AUTHOR]

• This two-step precise targeting nanoplatform could realize the site-specific release of different drugs. • Apoptosis was caused by utilizing the organelle's own characteristics. • Two drugs with different mechanisms achieve the purpose of synergistic anti-tumor. With the in-depth research of organelles, the microenvironment characteristics of their own, such as the acid environment of lysosomes and the high temperature environment of mitochondria, could be used as a natural and powerful condition for tumor therapy. Based on this, we constructed a two-step precise targeting nanoplatform which can realize the drug release and drug action triggered by the microenvironment of lysosomes (endosomes) and mitochondria, respectively. To begin with, the mesoporous silica nanoparticles (MSNs) were modified with triphenylphosphonium (TPP) and loaded with 2,2′-azobis[2-(2-imidazolin-2-yl) propane] dihydrochloride (AIPH). Then, folic acid (FA) targeted pH-sensitive liposomes containing docetaxel (Lipo/DTX-FA) were prepared by thin-film dispersion method, and the core-shell AIPH/MSN-TPP@Lipo/DTX-FA nanoparticles were constructed by self-assembly during the hydration of the liposomes. When this nanoplatform entered into the tumor cells through FA receptor-mediated endocytosis, the pH-sensitive liposomes were destabilized in the lysosomes, resulting in the release of DTX and AIPH/MSN-TPP nanoparticles. After that, AIPH was delivered to mitochondria by AIPH/MSN-TPP, and the alkyl radicals produced by AIPH under the high temperature environment can cause oxidative damage to mitochondria. Not only that, the DTX could enhance the anti-tumor effect of AIPH by downregulating the expression of anti-apoptotic Bcl-2 protein. The in vitro and in vivo results demonstrate that this delivery system could induce apoptosis based on organelles' s own microenvironment, which provides a new approach for tumor therapy. [ABSTRACT FROM AUTHOR]

• Yeast extract amino acids can shape the fermentation microbiota of soy sauce. • Yeast extract amino acids boost the competitiveness of aroma-producing microbiota. • The best mass ratio of neutral: acidic: basic amino acids is 58:27:15. • The best amino acid formula can increase the malt aroma of soy sauce by 52.6%. Yeast extracts, of which amino acids are the main component, can be directly applied to improve the flavor of final soy sauce. In this study, the potential of commercial yeast extracts was explored from amino acid approach to enhance the flavor quality of soy sauce by shaping the core fermentation microbiota. Alkaline and neutral amino acids favored the competitive benefits of flavor-producing bacteria, while acidic amino acids promoted the stress resistance of the fermentation microbiota, especially the abundance of Lactobacillus , which increased to 18.03–23.78% and became the predominant microbiota. The mass ratio of neutral-nonpolar: neutral-polar: acidic: alkaline amino acids was 40: 18: 27: 15, which provided the optimal improvement of soy sauce aroma. The formulation and activated the metabolic pathways of 3-methyl-1-butyraldehyde, 3-methyl-1-butanol and 2-methyl-1-propanol through Leu and Ile, resulting in a 52.6% increase in malt-like aroma. This study provides a new idea for the regulation of soy sauce fermentation. [ABSTRACT FROM AUTHOR]

Vinegar is a kind of fermented food condiments, which includes many regional products and involves abundant microbial resources. However, spontaneous fermentation cannot ensure consistent quality of vinegar, relatively little is known about the complexity of the microbiota involved in quality. Therefore, this review aim to explore that the role of microbiota in sediments, flavor compounds and bioactive substances. On this basis, we determined that raw materials, initial microbial composition and environmental factors are the driving forces of the fermentation process. Furthermore, we have revealed the core microorganism reaction mechanism under the driving forces. It can guide the design of the microbiota for vinegar fermentation, and to ensure the consistent of vinegar quality. This review will provide control strategies to monitor, control, and improve the safety, flavor, and health benefits of vinegar. [Display omitted] • To reveal the microbial metabolic network of vinegar quality. • The driving forces affecting the spontaneous fermentation are put forward. • The control biotransformation mechanisms through driving forces are obtained. • Driving forces physiological feedback guides the design of core microorganisms. [ABSTRACT FROM AUTHOR]

Steam explosion (SE) can improve the degradation efficiency of macromolecules such as defatted soybean meal (DSM). In this study, the physicochemical properties and the fermentation characteristics of SE-pretreated DSM were investigated. As shown by scanning electron microscopy (SEM), the dense structure of DSM was clearly cracked with larger voids. Under the pressure of 1.5 MPa, cellulose and hemicellulose were degraded by 50.7% and 71.1% respectively. When DSM treated with different SE pressure was applied to the soy sauce fermentation process, the content of amino acid nitrogen was increased 2-folds higher compared to the control, and the fermentation time has been greatly reduced. Simultaneously, the alcohols content of SS-1.5 sample was more than three times that of the control, particularly in the production of higher alcohols such as 2-methyl-1-butanol. The aldehydes, which contribute to the fruity and smoky-like aroma of soy sauce, increased significantly in both content and types (e.g., decanal, isobutyraldehyde, and 2-methylbutyraldehyde). The typical umami flavor and sauce-like aroma of soy sauce were considerably improved after SE-pretreated DSM. Taken together, SE pretreatment improved the utilization rate of raw materials and the quality of soy sauce flavor. [Display omitted] • Steam explosion (SE) destroys the structure of defatted soybean meal (DSM). • SE pretreatment enhances the soy sauce volatile flavor compounds. • SE pretreatment shortens the fermentation time of soy sauce by half. • The contents of reducing sugar and amino acid nitrogen were increased. [ABSTRACT FROM AUTHOR]

The presence of gas-producing bacteria in sufu will cause the package swelling, thus significantly affecting the storage period and sensory quality of sufu. This study aimed to isolate and identify the gas-producing bacteria in sufu and provide an effective method to control their growth. The gas-producing bacteria were isolated in sufu and identified as Weissella confusa and Weissella koreensis based on 16S rDNA. W. confusa and W. koreensis still grow and produce gas in MRS broth with a salinity of 10% oralcohol of 11% content. Nisin and Lactococcus lacti s were able to inhibit the growth of W. confusa and W. koreensis, while no inhibition was observed when sodium propionate, sodium dehydroacetate, and ε-polylysine hydrochloride were used. When the salinity and alcohol content was 6%, the growth of W. confusa was inhibited at MICs of nisin of 0.250 mg mL−1 and 0.125 mg mL−1, while the growth of W. koreensis was inhibited to 0.125 mg mL−1 and 0.063 mg mL−1. Nisin and L. lactis induced changes in cell morphology by disrupting membrane integrity of gas-producing bacteria. This study guides the sufu enterprises to adopt effective measures controlling the package swelling of sufu production and extending the products' storage period. ● Two gas-producing bacteria were isolated and identified in sufu. ● Weissella confuse and Weissella koreensis were tolerance in salinity of 10% or alcohol of 11% content. ● Nisin and Lactococcus lactis inhibited the growth of gas-producing bacteria ● Nisin and L. lactis disrupted the cell membrane integrity of gas-producing bacteria [ABSTRACT FROM AUTHOR]